xref: /linux/arch/x86/include/asm/io.h (revision da1d9caf95def6f0320819cf941c9fd1069ba9e1)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_IO_H
3 #define _ASM_X86_IO_H
4 
5 /*
6  * This file contains the definitions for the x86 IO instructions
7  * inb/inw/inl/outb/outw/outl and the "string versions" of the same
8  * (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
9  * versions of the single-IO instructions (inb_p/inw_p/..).
10  *
11  * This file is not meant to be obfuscating: it's just complicated
12  * to (a) handle it all in a way that makes gcc able to optimize it
13  * as well as possible and (b) trying to avoid writing the same thing
14  * over and over again with slight variations and possibly making a
15  * mistake somewhere.
16  */
17 
18 /*
19  * Thanks to James van Artsdalen for a better timing-fix than
20  * the two short jumps: using outb's to a nonexistent port seems
21  * to guarantee better timings even on fast machines.
22  *
23  * On the other hand, I'd like to be sure of a non-existent port:
24  * I feel a bit unsafe about using 0x80 (should be safe, though)
25  *
26  *		Linus
27  */
28 
29  /*
30   *  Bit simplified and optimized by Jan Hubicka
31   *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999.
32   *
33   *  isa_memset_io, isa_memcpy_fromio, isa_memcpy_toio added,
34   *  isa_read[wl] and isa_write[wl] fixed
35   *  - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
36   */
37 
38 #define ARCH_HAS_IOREMAP_WC
39 #define ARCH_HAS_IOREMAP_WT
40 
41 #include <linux/string.h>
42 #include <linux/compiler.h>
43 #include <linux/cc_platform.h>
44 #include <asm/page.h>
45 #include <asm/early_ioremap.h>
46 #include <asm/pgtable_types.h>
47 #include <asm/shared/io.h>
48 
49 #define build_mmio_read(name, size, type, reg, barrier) \
50 static inline type name(const volatile void __iomem *addr) \
51 { type ret; asm volatile("mov" size " %1,%0":reg (ret) \
52 :"m" (*(volatile type __force *)addr) barrier); return ret; }
53 
54 #define build_mmio_write(name, size, type, reg, barrier) \
55 static inline void name(type val, volatile void __iomem *addr) \
56 { asm volatile("mov" size " %0,%1": :reg (val), \
57 "m" (*(volatile type __force *)addr) barrier); }
58 
59 build_mmio_read(readb, "b", unsigned char, "=q", :"memory")
60 build_mmio_read(readw, "w", unsigned short, "=r", :"memory")
61 build_mmio_read(readl, "l", unsigned int, "=r", :"memory")
62 
63 build_mmio_read(__readb, "b", unsigned char, "=q", )
64 build_mmio_read(__readw, "w", unsigned short, "=r", )
65 build_mmio_read(__readl, "l", unsigned int, "=r", )
66 
67 build_mmio_write(writeb, "b", unsigned char, "q", :"memory")
68 build_mmio_write(writew, "w", unsigned short, "r", :"memory")
69 build_mmio_write(writel, "l", unsigned int, "r", :"memory")
70 
71 build_mmio_write(__writeb, "b", unsigned char, "q", )
72 build_mmio_write(__writew, "w", unsigned short, "r", )
73 build_mmio_write(__writel, "l", unsigned int, "r", )
74 
75 #define readb readb
76 #define readw readw
77 #define readl readl
78 #define readb_relaxed(a) __readb(a)
79 #define readw_relaxed(a) __readw(a)
80 #define readl_relaxed(a) __readl(a)
81 #define __raw_readb __readb
82 #define __raw_readw __readw
83 #define __raw_readl __readl
84 
85 #define writeb writeb
86 #define writew writew
87 #define writel writel
88 #define writeb_relaxed(v, a) __writeb(v, a)
89 #define writew_relaxed(v, a) __writew(v, a)
90 #define writel_relaxed(v, a) __writel(v, a)
91 #define __raw_writeb __writeb
92 #define __raw_writew __writew
93 #define __raw_writel __writel
94 
95 #ifdef CONFIG_X86_64
96 
97 build_mmio_read(readq, "q", u64, "=r", :"memory")
98 build_mmio_read(__readq, "q", u64, "=r", )
99 build_mmio_write(writeq, "q", u64, "r", :"memory")
100 build_mmio_write(__writeq, "q", u64, "r", )
101 
102 #define readq_relaxed(a)	__readq(a)
103 #define writeq_relaxed(v, a)	__writeq(v, a)
104 
105 #define __raw_readq		__readq
106 #define __raw_writeq		__writeq
107 
108 /* Let people know that we have them */
109 #define readq			readq
110 #define writeq			writeq
111 
112 #endif
113 
114 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
115 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
116 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
117 
118 /**
119  *	virt_to_phys	-	map virtual addresses to physical
120  *	@address: address to remap
121  *
122  *	The returned physical address is the physical (CPU) mapping for
123  *	the memory address given. It is only valid to use this function on
124  *	addresses directly mapped or allocated via kmalloc.
125  *
126  *	This function does not give bus mappings for DMA transfers. In
127  *	almost all conceivable cases a device driver should not be using
128  *	this function
129  */
130 
131 static inline phys_addr_t virt_to_phys(volatile void *address)
132 {
133 	return __pa(address);
134 }
135 #define virt_to_phys virt_to_phys
136 
137 /**
138  *	phys_to_virt	-	map physical address to virtual
139  *	@address: address to remap
140  *
141  *	The returned virtual address is a current CPU mapping for
142  *	the memory address given. It is only valid to use this function on
143  *	addresses that have a kernel mapping
144  *
145  *	This function does not handle bus mappings for DMA transfers. In
146  *	almost all conceivable cases a device driver should not be using
147  *	this function
148  */
149 
150 static inline void *phys_to_virt(phys_addr_t address)
151 {
152 	return __va(address);
153 }
154 #define phys_to_virt phys_to_virt
155 
156 /*
157  * Change "struct page" to physical address.
158  */
159 #define page_to_phys(page)    ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
160 
161 /*
162  * ISA I/O bus memory addresses are 1:1 with the physical address.
163  * However, we truncate the address to unsigned int to avoid undesirable
164  * promotions in legacy drivers.
165  */
166 static inline unsigned int isa_virt_to_bus(volatile void *address)
167 {
168 	return (unsigned int)virt_to_phys(address);
169 }
170 #define isa_bus_to_virt		phys_to_virt
171 
172 /*
173  * However PCI ones are not necessarily 1:1 and therefore these interfaces
174  * are forbidden in portable PCI drivers.
175  *
176  * Allow them on x86 for legacy drivers, though.
177  */
178 #define virt_to_bus virt_to_phys
179 #define bus_to_virt phys_to_virt
180 
181 /*
182  * The default ioremap() behavior is non-cached; if you need something
183  * else, you probably want one of the following.
184  */
185 extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size);
186 #define ioremap_uc ioremap_uc
187 extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
188 #define ioremap_cache ioremap_cache
189 extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size, unsigned long prot_val);
190 #define ioremap_prot ioremap_prot
191 extern void __iomem *ioremap_encrypted(resource_size_t phys_addr, unsigned long size);
192 #define ioremap_encrypted ioremap_encrypted
193 
194 /**
195  * ioremap     -   map bus memory into CPU space
196  * @offset:    bus address of the memory
197  * @size:      size of the resource to map
198  *
199  * ioremap performs a platform specific sequence of operations to
200  * make bus memory CPU accessible via the readb/readw/readl/writeb/
201  * writew/writel functions and the other mmio helpers. The returned
202  * address is not guaranteed to be usable directly as a virtual
203  * address.
204  *
205  * If the area you are trying to map is a PCI BAR you should have a
206  * look at pci_iomap().
207  */
208 void __iomem *ioremap(resource_size_t offset, unsigned long size);
209 #define ioremap ioremap
210 
211 extern void iounmap(volatile void __iomem *addr);
212 #define iounmap iounmap
213 
214 #ifdef __KERNEL__
215 
216 void memcpy_fromio(void *, const volatile void __iomem *, size_t);
217 void memcpy_toio(volatile void __iomem *, const void *, size_t);
218 void memset_io(volatile void __iomem *, int, size_t);
219 
220 #define memcpy_fromio memcpy_fromio
221 #define memcpy_toio memcpy_toio
222 #define memset_io memset_io
223 
224 #include <asm-generic/iomap.h>
225 
226 /*
227  * ISA space is 'always mapped' on a typical x86 system, no need to
228  * explicitly ioremap() it. The fact that the ISA IO space is mapped
229  * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
230  * are physical addresses. The following constant pointer can be
231  * used as the IO-area pointer (it can be iounmapped as well, so the
232  * analogy with PCI is quite large):
233  */
234 #define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))
235 
236 #endif /* __KERNEL__ */
237 
238 extern void native_io_delay(void);
239 
240 extern int io_delay_type;
241 extern void io_delay_init(void);
242 
243 #if defined(CONFIG_PARAVIRT)
244 #include <asm/paravirt.h>
245 #else
246 
247 static inline void slow_down_io(void)
248 {
249 	native_io_delay();
250 #ifdef REALLY_SLOW_IO
251 	native_io_delay();
252 	native_io_delay();
253 	native_io_delay();
254 #endif
255 }
256 
257 #endif
258 
259 #define BUILDIO(bwl, bw, type)						\
260 static inline void out##bwl##_p(type value, u16 port)			\
261 {									\
262 	out##bwl(value, port);						\
263 	slow_down_io();							\
264 }									\
265 									\
266 static inline type in##bwl##_p(u16 port)				\
267 {									\
268 	type value = in##bwl(port);					\
269 	slow_down_io();							\
270 	return value;							\
271 }									\
272 									\
273 static inline void outs##bwl(u16 port, const void *addr, unsigned long count) \
274 {									\
275 	if (cc_platform_has(CC_ATTR_GUEST_UNROLL_STRING_IO)) {		\
276 		type *value = (type *)addr;				\
277 		while (count) {						\
278 			out##bwl(*value, port);				\
279 			value++;					\
280 			count--;					\
281 		}							\
282 	} else {							\
283 		asm volatile("rep; outs" #bwl				\
284 			     : "+S"(addr), "+c"(count)			\
285 			     : "d"(port) : "memory");			\
286 	}								\
287 }									\
288 									\
289 static inline void ins##bwl(u16 port, void *addr, unsigned long count)	\
290 {									\
291 	if (cc_platform_has(CC_ATTR_GUEST_UNROLL_STRING_IO)) {		\
292 		type *value = (type *)addr;				\
293 		while (count) {						\
294 			*value = in##bwl(port);				\
295 			value++;					\
296 			count--;					\
297 		}							\
298 	} else {							\
299 		asm volatile("rep; ins" #bwl				\
300 			     : "+D"(addr), "+c"(count)			\
301 			     : "d"(port) : "memory");			\
302 	}								\
303 }
304 
305 BUILDIO(b, b, u8)
306 BUILDIO(w, w, u16)
307 BUILDIO(l,  , u32)
308 #undef BUILDIO
309 
310 #define inb_p inb_p
311 #define inw_p inw_p
312 #define inl_p inl_p
313 #define insb insb
314 #define insw insw
315 #define insl insl
316 
317 #define outb_p outb_p
318 #define outw_p outw_p
319 #define outl_p outl_p
320 #define outsb outsb
321 #define outsw outsw
322 #define outsl outsl
323 
324 extern void *xlate_dev_mem_ptr(phys_addr_t phys);
325 extern void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr);
326 
327 #define xlate_dev_mem_ptr xlate_dev_mem_ptr
328 #define unxlate_dev_mem_ptr unxlate_dev_mem_ptr
329 
330 extern int ioremap_change_attr(unsigned long vaddr, unsigned long size,
331 				enum page_cache_mode pcm);
332 extern void __iomem *ioremap_wc(resource_size_t offset, unsigned long size);
333 #define ioremap_wc ioremap_wc
334 extern void __iomem *ioremap_wt(resource_size_t offset, unsigned long size);
335 #define ioremap_wt ioremap_wt
336 
337 extern bool is_early_ioremap_ptep(pte_t *ptep);
338 
339 #define IO_SPACE_LIMIT 0xffff
340 
341 #include <asm-generic/io.h>
342 #undef PCI_IOBASE
343 
344 #ifdef CONFIG_MTRR
345 extern int __must_check arch_phys_wc_index(int handle);
346 #define arch_phys_wc_index arch_phys_wc_index
347 
348 extern int __must_check arch_phys_wc_add(unsigned long base,
349 					 unsigned long size);
350 extern void arch_phys_wc_del(int handle);
351 #define arch_phys_wc_add arch_phys_wc_add
352 #endif
353 
354 #ifdef CONFIG_X86_PAT
355 extern int arch_io_reserve_memtype_wc(resource_size_t start, resource_size_t size);
356 extern void arch_io_free_memtype_wc(resource_size_t start, resource_size_t size);
357 #define arch_io_reserve_memtype_wc arch_io_reserve_memtype_wc
358 #endif
359 
360 #ifdef CONFIG_AMD_MEM_ENCRYPT
361 extern bool arch_memremap_can_ram_remap(resource_size_t offset,
362 					unsigned long size,
363 					unsigned long flags);
364 #define arch_memremap_can_ram_remap arch_memremap_can_ram_remap
365 
366 extern bool phys_mem_access_encrypted(unsigned long phys_addr,
367 				      unsigned long size);
368 #else
369 static inline bool phys_mem_access_encrypted(unsigned long phys_addr,
370 					     unsigned long size)
371 {
372 	return true;
373 }
374 #endif
375 
376 /**
377  * iosubmit_cmds512 - copy data to single MMIO location, in 512-bit units
378  * @dst: destination, in MMIO space (must be 512-bit aligned)
379  * @src: source
380  * @count: number of 512 bits quantities to submit
381  *
382  * Submit data from kernel space to MMIO space, in units of 512 bits at a
383  * time.  Order of access is not guaranteed, nor is a memory barrier
384  * performed afterwards.
385  *
386  * Warning: Do not use this helper unless your driver has checked that the CPU
387  * instruction is supported on the platform.
388  */
389 static inline void iosubmit_cmds512(void __iomem *dst, const void *src,
390 				    size_t count)
391 {
392 	const u8 *from = src;
393 	const u8 *end = from + count * 64;
394 
395 	while (from < end) {
396 		movdir64b(dst, from);
397 		from += 64;
398 	}
399 }
400 
401 #endif /* _ASM_X86_IO_H */
402